Mark Halperin was born in 1965 in New York City and raised in Bethesda, Maryland.
Mark started out as a desk assistant for ABC News in 1988 and slowly worked his way up to being a political director for ABC News (in 1997). In March 2007, Halperin became a political analyst for ABC News and then, in 2010, MSNBC hired Mark as a senior political analyst.
In 2017, NBC and MSNBC terminated all contracts with Mark Halperin due to some controversies surrounding Mark. You can read more about it on Wikipedia.